Quiz Entry - updated: 2026.07.14
What are the four key features of TCP?
TCP (1) establishes a session, (2) ensures reliable delivery, (3) provides same-order delivery, and (4) supports flow control.
Four Key TCP Features:
| Feature | Description |
|---|---|
| Establishes a Session | Creates a connection before forwarding any traffic |
| Ensures Reliable Delivery | Guarantees all segments arrive; retransmits lost data |
| Provides Same-Order Delivery | Numbers segments so receiver can reassemble in original order |
| Supports Flow Control | Regulates data flow to prevent receiver overload |
How TCP achieves reliability:
- Numbers and tracks data segments
- Acknowledges received data
- Retransmits any unacknowledged data after timeout
- Sequences data that might arrive in wrong order
Analogy: TCP is like sending tracked packages - you can monitor delivery status and the recipient confirms receipt.
Go deeper:
RFC 9293 — Transmission Control Protocol — the current authoritative TCP spec covering session setup, reliability, ordering, and flow control.- TCP — Protocol operation — Wikipedia summary of how these four guarantees are implemented.